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951.
L. A. Lapkina Yu. G. Gorbunova S. E. Nefedov A. Yu. Tsivadze 《Russian Chemical Bulletin》2003,52(7):1633-1636
952.
The transformation of a shear surface magnetoelastic wave by the motion of the 180° confining domain wall in a ferromagnet is considered. Changes in the wave spectrum due to the motion of the wall are correlated with the variations of the energies of the elastic and magnetic subsystems. The efficiency of surface wave transformation by the domain wall motion is estimated in terms of energy. The frequency dependences of the mean energy density of the wave are found. It is shown that the energy density grows with wall velocity. 相似文献
953.
954.
In this paper we describe the experimental analysis of a novel ion-exchange polymer metal composite (IPMC) actuator under
large external voltage. The experimental analysis is supplemented with a coupled thermodynamic model, which includes mass
transport across the thickness of the polymer actuator, chemical reactions at boundaries, and deformation as a function of
the solvent (water) distribution. In this paper, the case of large electrode potentials (over 1.2 V) has been analyzed experimentally
and theoretically. At these voltage levels, electrochemical reactions take place at both electrodes. These are used in the
framework of overpotential theory to develop boundary conditions for the water transport in the bulk of polymer. The model
is then simplified to a three-component system comprised of a fixed negatively charged polymeric matrix, protons, and free
water molecules within the polymer matrix. Among these species, water molecules are considered to be the dominant species
responsible for the deformation of the IPMC actuators. Experiments conducted at different initial water contents are described
and discussed in the context of the proposed deformation mechanism. Comparison of numerical simulations with experimental
data shows good agreement. 相似文献
955.
E. V. Il'ina 《Computational Mathematics and Modeling》1993,4(1):90-94
Translated from Pryamye i Obratnye Zadachi Matematicheskoi Fiziki, pp. 198–203, 1991. 相似文献
956.
M. I. Dykman D. G. Luchinsky R. Mannella P. V. E. McClintock N. D. Stein N. G. Stocks 《Il Nuovo Cimento D》1995,17(7-8):661-683
Summary We outline the historical development of stochastic resonance (SR), a phenomenon in which the signal and/or the signal-to-noise
ratio in a nonlinear system increase with increasing intensity of noise. We discuss basic theoretical ideas explaining and
describing SR, and we review some revealing experimental data that place SR within the wider context of statistical physics.
We emphasize the close relationship of SR to some effects that are well known in condensed-matter physics.
Paper presented at the International Workshop ?Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena?, Elba, 5–10 June 1994. 相似文献
957.
Multi-valued solutions are constructed for 2 × 2 first-order systems using a generalization of the hodograph transformation. The solution is found as a complex analytic function on a complex Riemann surface for which the branch points move as part of the solution. The branch point singularities are envelopes for the characteristics and thus move at the characteristic speeds. We perform an analysis of stability of these singularities with respect to perturbations of the initial data. The generic singularity types are folds, cusps, and nondegenerate umbilic points with non-zero 3-jet. An isolated singularity is generically a square root branch point corresponding to a fold. Two types of collisions between singularities are generic: At a “tangential” collision between two singularities moving at the same characteristic speed, a cube root branch point is formed, corresponding to a cusp. A “non-tangential” collision, between two square root branch points moving at different characteristic speeds, remains a square root branch point at the collision and corresponds to a nondegenerate umbilic point. These results are also valid for a diagonalizable n-th order system for which there are exactly two speeds. © 1993 John Wiley & Sons, Inc. 相似文献
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